Police and gun control advocates today sounded a louder call for politicians to take a stand against gun violence - despite Congress's lack of political will to touch the issue, or the White House's affirmation that President Obama had no plans to put new gun laws on the books.

"We have refused to accept silence from the candidates for the highest office in our land," Dan Gross, president of the Brady Campaign to Prevent Gun Violence, told reporters today at the National Press Club.

"The American people have shown overwhelmingly that they are ready to have a real conversation about how to prevent gun violence, and we are demanding the same from our elected representatives: Not to play politics but to lead."

The nation's largest anti-gun violence group, the Brady Campaign, was founded by President Reagan's press secretary, Jim Brady, who was confined to a wheelchair after he took a bullet to the head in a Reagan assassination attempt in 1981.

The group supports broadening the Brady Law, enacted in 1994, which requires federally licensed firearms dealers to run background checks on would-be buyers to weed out felons, drug addicts or others who might prove dangerous. But today, the group put policy on hold and instead urged Obama and presumptive Republican nominee Mitt Romney to take the lead in discussing ways to end gun violence, whatever they might be.

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"It is time for all of us to come together - Republicans, Democrats, blue states, red states, people who own guns and people who don't - to have a meaningful national conversation about what we can do about it," Gross said. "I think it's shameful that our political leaders would play politics when there are lives that can be saved."

More than 30 people die of gun-related violence every day in the U.S., according to the Brady Campaign. If that number holds steady, 48,000 Americans will be victims of gun violence during the next presidential term.

"We truly believe, as a nation, we are better than this," Gross said.

Less than a week after a movie theater massacre in Aurora, Colo., left 12 dead and 58 injured, a national group of police associations also took to Washington, D.C., to drum up support for more gun control measures.

The National Law Enforcement Partnership to Prevent Gun Violence, a group of nine national police associations, today echoed its demands for background checks on all firearms purchasers.

"America, we are not doing enough to keep guns out of the wrong hands," said James Johnson, Baltimore county chief of police and incoming chairman of the partnership. "We are long past the point of saying 'enough is enough.' The mantra has grown old. It's time to take action to keep firearms from dangerous people."

The Brady Law applies only to federally licensed gun dealers - which accounts for 60 percent of all U.S. firearm transactions, according to the partnership. People who buy assault-style guns or high-capacity ammunition online, or through a classified ad, for example, might not be subject to those background checks.

Aurora shooting suspect James Holmes did pass background checks to purchase his guns legally, partnership president Hubert Williams acknowledged. But broadening the law would help close a "gaping hole" that illegal buyers can still exploit, he said.

"We're not asking for new laws. We're asking for existing laws to be enforced on all people that are purchasing these weapons," Williams said. "We're just saying that the law has a loophole in it that needs to be plugged."

Gross, of the Brady Campaign, said it's important for politicians to talk about gun control - but just paying lip service isn't enough.

"A speech is not a plan. An endorsement of a measure is not a solution," he said. "We want a plan with solutions."